A former member of the Ukrainian parliament says special counsel Robert Mueller grilled him last week about his interactions with President Donald Trump's embattled personal lawyer Michael Cohen, The Washington Post reported.

Cohen is already under scrutiny from federal prosecutors in Manhattan who are examining his business practices.

But Andrii Artemenko, a former Ukrainian parliament member, told the Post many of the questions he faced during several hours of testimony last Friday were focused on his interactions with Cohen.

"I realized that Michael Cohen is a target" of special interest to Mueller, Artemenko told the Post days after he was questioned.

Artemenko met with Cohen in January 2017 to discuss a back-channel peace initiative for Ukraine, a meeting that was organized by Trump's business associate Felix Sater, the Post reported.

He said the proposed plan would have ended the conflict in Ukraine and eventually lifted U.S. sanctions placed on Russia.

But the men deny the meeting was friendly toward Russia. The two men and Cohen have given different public accounts of the meeting, the Post reported.

According to the Post, Cohen asserts Artemenko said Russia supported his Ukrainian peace plan; Artemenko said the Russian government was not involved in the initiative.

After his meeting with Cohen was reported, Artemenko was expelled from the Ukrainian parliament and stripped of his citizenship.

Artemenko, who now lives in Canada, told the Post his intentions in meeting with Cohen were misconstrued, telling the Post, "My destiny, my main goal, is to bring peace to Ukraine."

An expelled member of the Ukrainian parliament says special counsel Robert Mueller grilled him last week about his interactions with President Donald Trump's embattled personal lawyer Michael Cohen, according to The Washington Post.